Scientists Want to Build a Laser to Lead Aliens to Earth

Scientists know that there are millions... perhaps billions, of planets in the universe that could sustain life. Is the universe too big, or spread out, to communicate with any of them? Or are aliens deliberately ignoring us Earthlings?

Science is not done trying. The Astrophysical Journal published yesterday that it is doable to send signals to space, in the effort to communicate with extraterrestrial intelligence.

This infrared laser would be bright enough that if it were to be shined directly at nearby exoplanets, “alien astronomers should be able to detect it with sky-watching technology.”

The researchers proposed a design that would require a 1 to 2 megawatt laser and a 100-foot (at least) diameter primary mirror.

James Clark, the lead author on the paper, said that is isn’t clear if aliens would immediately recognize the laser as a signal from us, or another intelligent life-form, but that "it would certainly attract attention."

The authors wrote that Earth is a relatively minor planet, of eight planets, “orbiting a star much brighter than any laser humanity could reasonably hope to produce.” This would be the hardest part. But, if we’ve been on the moon, isn’t anything possible?

The worry is that, for an alien astronomer hundreds of light years away, any infrared source might be muted by the immensely white-hot source of light in “our local space.”

This is why the laser wouldn’t be a blinking guide, but a source of light to make our sun look strange enough from an alien perspective, that they would want to take a second look.

However, if we were to point a laser of the scale that Clark imagines, our sun might show unusual activity.

If aliens did detect our signal, and could process the significance of it, there is a possibility to set up a communication channel. These lasers have data transfer rates of up to 2 Megabites per second, which is similar to a slow internet connection. However, even with this amazing technological advance, there would of course be time delays of decades between the messages being received and sent.

The researchers found that the laser could still be used and detected farther away from earth, to about 200,000 light-years away. This range would only reach other stars in our general region of the Milky Way.

The possible risks of this operation, if all run smoothly, make many Earthlings nervous. Some, however, are excited.

Perhaps some day in the future our internet ads will say "Local Single Aliens, Near You!"